In Wireless Sensor Networks (WSN), neglecting the
effects of varying channel quality can lead to an
unnecessary wastage of precious battery resources and in
turn can result in the rapid depletion of sensor energy and
the partitioning of the network. Fairness is a critical issue
when accessing a shared wireless channel and fair
scheduling must be employed to provide the proper flow
of information in a WSN. In this paper, we develop a
channel adaptive MAC protocol with a traffic-aware
dynamic power management algorithm for efficient packet
scheduling and queuing in a sensor network, with time
varying characteristics of the wireless channel also taken
into consideration. The proposed protocol calculates a
combined weight value based on the channel state and link
quality. Then transmission is allowed only for those nodes
with weights greater than a minimum quality threshold
and nodes attempting to access the wireless medium with a
low weight will be allowed to transmit only when their
weight becomes high. This results in many poor quality
nodes being deprived of transmission for a considerable
amount of time. To avoid the buffer overflow and to
achieve fairness for the poor quality nodes, we design a
Load prediction algorithm. We also design a traffic aware
dynamic power management scheme to minimize the
energy consumption by continuously turning off the radio
interface of all the unnecessary nodes that are not included
in the routing path. By Simulation results, we show that
our proposed protocol achieves a higher throughput and
fairness besides reducing the delay

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IJCSNS International Journal of Computer Science and Network Security, VOL.10 No.7, July 2010